How to leverage Vector Index for Search on existing Neo4j database with production data?

Hello

How can someone leverage their existing production db with vector index and searching on top of it. Most of the example create schema and index from scratch using unstructured data.

We have a defined schema with over 450k nodes and 6.6M relationships.
We want to enable similarity search over vector index to answer questions.

Are there any resources that can help?

Thank you